#include <iostream>  
using namespace std;

class Line
{
public:
    void setLength( double len );  
    double getLength( void );
    double pi;
private:
    double length;
    double age;
    
};

// 成员函数定义
double Line::getLength(void)
{
    return length ;
}

void Line::setLength( double len )
{
    length = len;
}


int main()
{
    Line myline;
    //myline.length = 5.0;
    myline.setLength(5.0);
    cout<<myline.getLength()<<endl;
    return 0;
}
